PQ is tangent to the circle at C. In the circle the measure of arc v equals 85 I need an explanation for this please I've got a big problem here​

Which expression is equivalent to √ -80?

Kathy spent 5/8 of her money on books and another 1/6 of her money on stationeries.what fraction of kathy’s money was left?

What is the value of the discriminant of the quadratic equation -2x = -8x + 8 and what does its value mean about thenumber of real number solutions the equation has?